In a 136-page report, the Inter-American Commission on Human Rights called the open-ended detention of non-American terrorist suspects at Guantanamo “a clear violation of international law.”

“Reasons of public security cannot serve as a pretext for the indefinite detention of individuals without charge or trial,” it said.

The report comes two weeks after the White House said it was in the “final stages” of drafting a plan to shut down the military-run prison that will be submitted to Congress for review.

President Barack Obama made the closure of the controversial prison in Cuba a priority when he took office in 2009.

But attempts to fulfil that pledge has faced numerous setbacks, including Congress blocking the transfer of detainees to US prisons.

Guantanamo opened in January 2002 on the heels of the September 11, 2001 attacks on New York`s World Trade Center and the Pentagon in Washington.

After reaching a peak of 680 prisoners in 2003, there are 116 detainees remaining. All are Muslim.

The Inter-American Commission insisted on detainees being held in line with international human rights standards, with adequate health care and freedom of religion respected.

It recommended that the United States “declassify all evidence of torture and ill-treatment” and halt the force-feeding of hunger strikers.

Regarding access to justice, it called for Guantanamo detainees who face prosecution before military commissions be put on trial instead in federal courts.

In doing so, due process — a major concern with military commissions — must be upheld, it said.

“Courts must undertake a rigorous examination of the government`s evidence to ensure that any detention in this context is based on clear and convincing evidence,” it said.

“A decision of the US Supreme Court could shed light on whether Guantanamo detainees are being afforded a meaningful opportunity to challenge the legality of their detention.”

Ultimately, the Inter-American Commission said the Guantanamo detention center — situated within a US naval base in eastern Cuba — needs to be shut down once and for all.

Its detainees should either be transferred to the United States for prosecution, incarceration and medical treatment, it said, or sent back to their countries of origin or to third countries if their lives and freedoms might be at risk.

Emilio Alvarez-Icaza, the Inter-American Commission`s executive director, said: “We believe that this report will be very important … as it adds new elements and new arguments to proceed with the closure of the detention center.”